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CastelliThermoflex 2 Knee Warmer


Item # CST00UL

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  • Black, S ($44.99)
  • Black, M ($44.99)
  • Black, L ($44.99)
  • Black, XL ($44.99)
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Item # CST00UL

Thermoflex 2 Knee Warmer

Throw on your favorite bib shorts and grab a set of the Castelli Thermoflex 2 Knee Warmers and enjoy a bit of extra protection from the cold when you're cycling in the shoulder seasons. The Thermoflex fleece fabric is warm, stretchy, and soft, and is constructed using flat-lock seams in order to alleviate any irritation or discomfort.

  • Protect your knees on chilly rides with these soft warmers
  • Thermoflex fleece provides warmth and next-to-skin comfort
  • One-piece design with flat-lock seams prevents irritation
  • Elastic cuff with gripper keeps them from sliding down

Tech Specs
MaterialThermoflex fleece
Recommended Useroad cycling
Manufacturer Warranty1 year


Arm & Knee Warmers





Rider Weight

99.2 - 132.3lb

(45 - 60kg)

99.2 - 132.3lb

(45 - 60kg)

132.3 - 154.3lb

(60 - 70kg)

154.3 - 176.4lb

(70 - 80kg)



Short/Jersey Size XS - S S - M S - M L - XL 2XL - 3XL
Short/Jersey Size:
Take your typical cycling short or bib sizing for comparison.

What do you think about this product?



huge disappointment follow up

adding pictures to my previous review of these new warmers....


huge disappointment follow up

adding pictures to my previous review of these new warmers....

>Rating: 1

Huge disappointment!

I've used it once or twice and have initial impressions
Runs large
Size Bought
5` 9"
180 lbs

First the sizing is all wrong; 1st I ordered L based on the sizing chart... Exchanged for M and they're still too big. Now the seam at the top where the thermal material meets the rubber material use to hold the warmer in place has come apart. Castelli use to be a premium brand; what happened? Now they're too old to return(just over a month old, worn one time) even tho they're defective... I guess i will need to call the manufacture for a replacement.

>Rating: 1

Disappointed in New Castelli Kneewarmers

I returned this product before using it
True to size

I have 2 pairs of Castelli Thermoflex Kneewarmers bought in early 2019 that I love and wear all the time! I wanted to order more, but only saw Thermoflex 2. Ordered 2 pairs. They are totally different and I cannot keep the bottoms from creeping up my calf to my knee. The previous versions were much longer with better grippers at both ends and totally stayed in place. Very diappointed; unusable! Will return the unused pair but unfortunately I wore one pair on a ride to test them out and 30 days has elapsed so I guess I am out of luck, seriously!